Many beverages like espresso and other coffee beverages, milk beverages, chocolate beverages, . . . are often prepared by mixing a food soluble powder or a food liquid concentrate with a diluent. Mixing devices are known for speedier preparation of such beverages by mixing the soluble food component with the diluent, such as water. These devices typically comprise a mixing chamber in which the soluble component and the diluent are fed. The diluent can be introduced into the dissolution chamber in order to create a whirlpool to efficiently dissolve the soluble component in the hot water or the hot diluent can be introduced under the form of jets that provides mixing, dissolving and frothing. The mixture can also eventually be frothed by a whipper in a whipping chamber to reconstitute the beverage and produce foam. The beverage is then usually evacuated from the mixing chamber through the bottom of the mixing chamber and dispensed into a receptacle for drinking.
The internal parts of the dispenser that are in contact with the diluted food component must be regularly cleaned to avoid the growth of bacteria due to residues of beverages in the machine and avoid clogging. This cleaning usually concerns at least the dissolution chamber and the whipping chamber which comprise several mechanical components. For cleaning operation, theses parts must be dismantled, then cleaned and then reassembled. This operation takes time and it must done by people that have been trained for the disassembling and the reassembling to avoid errors and further failure in the beverages production. Usually this cleaning is made by an operator dedicated to the maintenance of the beverages production machines.
Now there is need for decreasing the time for the cleaning operation to limit the perior of time during which the dispenser is not operable. There is also a need for having this operation made by any non trained person so that it is not necessary to ask a specific operator to come and clean the machine. The cleaning should be made by any person briefly trained on the cleaning operations. This cleaning operation must also be so short that he can be made more often depending on the nature of the food ingredients.
EP 2 105 076 proposes a beverage dispenser in which the cleaning operation is improved. This dispenser improves the easy dismantling of the different components of the dispenser in particular the housing and the back wall of the mixing chamber and the impeller. More precisely the easy dismantling consists in first separating the housing of the mixing chamber from the back wall of the mixing chamber and the impeller; the back wall of the mixing chamber remains fixed to the frame and the impeller remains anchored to the drive shaft. Then in a second step the housing of the mixing chamber is separated from the frame and by moving it from its mounted position to its dismounted position, the whipper is also moved towards the free end of the drive shaft and dismounted. The drive shaft presents a specific cross section or the impeller is made of a specific resilient material so that it cannot be moved out of the drive shaft by hand alone between the first and the second dismantling steps.
Although this dispenser enables an easy dismantling of the different components of the whipping unit, it presents several drawbacks. First it presents the risk of dirtying the dispenser during the first step of dismantling the whipper housing. Actually if the chamber still contains some liquid, then this liquid would fall downwards: it could fall from the mixing housing during its displacement from the machine to a work surface and from the back wall until it is also placed on the work surface. It could cause as lot of mess. Secondly with this dispenser the dismantling requires the operator to displace himself two times in front of the dispenser: for the first step and then for the second step. If the work surface for cleaning the whipping unit components is not just aside from the dispenser, the operator loses time. Thirdly in the dispenser of the prior art, the operator is not obliged to dismantle the back wall and the impeller from the frame, he can clean them on the frame. Yet such a cleaning is not optimal and the operator who wants to save time can tend towards never dismantling these elements from the frame and never operating a correct cleaning.
One aim of the present invention is to solve these problems and to propose a beverage dispenser comprising a whipping unit of which components can be easily and rapidly dismantled for cleaning.